Sandmill vessel

ABSTRACT

A vessel having an outer cylindrical jacket with flanges formed on its ends that position an inner liner which defines a processing chamber. The flanges are bolted to connecting rings which cooperate with the ends of the liner to support it and seal the processing chamber from the space between the jacket and the liner, while permitting easy replacement of the liner.

United States Patent [151 3,685,749 Brown [451 Aug. 22, 1972 [s41SANDMILL VESSEL [56] References Cited 7 [72] Inventor: Donald J.- Brown,La Crescenta, UNITED STATES PATENTS I 3,050,263 8/1962 Barkman et a1..241/m x [73] Aimigncc: Morehuugc Industries, Inc,, Fuller. 3,243,1283/1966 Tight ..24l/65 7 P Ex R bert L s u nmary ammer-- o PlLll [22]Wed: March 1971 Attorney-Fowler, Knobbe & Martens 2 A 1. N .2 12 37 DP 06 3 57 ABSTRACT A vessel having an outer cylindrical jacket with [52]US. Cl. ..24l/65, 241/74, 241/172 flanges formed on its ends thatposition an inner net [51] Int. Cl ..B02C 17/16 which defines aprocessing b The flanges are Field of Search ..241/65, 46.15, 74, 170,171,

bolted to connecting rings which cooperate with the ends of the liner tosupport it and seal the processing chamber from the space between thejacket and the liner, while permitting easy replacement of the liner.

4 Clains, Drawing Figures SANDMILL VESSEL This invention relates toapparatus for processing liquids and more particularly to an improvedconstruction for the vessel fomiing the processing chamber in apparatusknown as a sandmill. Sandmilling is a continuous high production methodof dispersing agglomerates such as pigments in film forming materials toproduce smooth, uniform, finely dispersed products. The process is usedin the manufacture of many types of critical-specification finishesincluding paints, inks, dye stuffs, coatings, insecticides andsimilar-products where a high degree of fineness is required. Such aprocess utilizes a mill having a processing chamber containing sand orother grinding media and a rotor for agitating the sand. The liquid tobe processed is pumped through the chamber as the sand is agitated.

The equipment employed in performing such process is subjected totheconstant abrasion .of the moving sand with the result that the metalwalls defining the processing chamber eventually become worn and must bereplaced. Since apparatus of this type is typically run continuously,replacement or repair of the worn portions can be required at relativelyfrequent intervals. The various types of liquid to which the chamberwalls are subjected can also contribute to erroding of the wallmaterial.

A sandmill vessel typically has a double wall construction with a heattransfer medium being circulated in the space between the two walls, andit is the inner wall or liner which forms the processing chambercontaining the sand that is subjected to the wearing action. Since theouter wall or jacket and other components of the overall apparatus arenot subjected to such wear, it is impractical to simply discard theentire machine when only the liner is worn. In known arrangements theliner is formed integral with the outer jacket, and it is necessary tocut the liner from the remainder of the apparatus with a torch or othercutting equipment, and it is then necessary to weld the new liner in itsproper position. These operations take considerable amount of time andhence are quite costly. Also, it is sometimes difficult to properlyposition the replacement liner in this fashion.

In accordance with the present invention, the sandmill vessel is formedof an improved construction wherein the inner liner is readily separablefrom the remainder of the vessel so that it can be easily replaced whenworn. More specifically, flanges are welded to the ends of the vesselouter jacket, the flanges extending radially inwardly and outwardly fromthe jacket wall. A cylindrical liner is positioned within the jacket todefine the processing chamber. The liner is spaced from the surroundingjacket by the inner portion of the flanges. A connecting ring attachedto the structure closing the ends of the chamber is bolted to eachflange, and each ring is formed with an annular groove for receiving theends of the liner. In this manner the liner is removably clamped inposition and is sealed from the space surrounding the processingchamber. As the liner becomes worn, the vessel can be easilydisassembled by unbolting the connecting rings with the result that itis much less expensive to replace a liner than with an all-weldedconstruction.

For a more detailed description of the invention,

reference may be had to the following specification and drawings inwhich:

FIG. l is a side elevational, partially sectionalized view of. thesandmill of the invention illustrating the construction of the vessel;and

FIG. 2 is across-sectional view on line 2-2 of P10. 1.

The sandmill of the invention may be seen to include a vessel 10'havingan outer cylindrical jacket 11 with thickened annular flanges 12 and 14welded to the opposite ends of the jacket. The lower flange 12 includesa main axially thickened portion 12 a having a notch in its outer uppercorner which is welded to the end and the adjacent inner surface of theouter jacket 11. The lower flange 12 includes an outer portion 12bhaving a series of circumferentially spaced axially extending threadedholes. The flange 12 further includes an axially extending rib 120formed on the inner lower corner of the main portion 120. The upperflange 14 is constructed and numbered similar to that of the flange 12except that is is inverted with respect to the lower flange.

A connecting ring 16 is bolted to the lower flange 12 by a plurality ofbolts 18 extending into the threaded holes of the flange portion 12b.The connecting ring 16 extends inwardly beyond the jacket 11 andincludes an annular groove 16a formed in its upper surface. Acylindrical liner 19 defining a processing chamber 20 is positionedwithin the jacket 11', spaced from the jacket by the flanges 12 and 14to form a space 21 for receiving a heat transfer medium such as coolingwater. As can be seen, the lower end of the liner 19 is positionedwithin the groove 16a together with the rib 12c on the flange l2, and aflat annular gasket 22.

A similar ring 23 is bolted to the upper flange l4 and is provided witha downwardly facing annular groove 23a. The upper end of the liner 19,the upstanding rib 14c and a flat annular gasket 24 are positionedwithin the groove 23a. From this construction, it can be seen that theliner 19 and the outer jacket 11, through its flanges, are compressedbetween the connecting rings 16 and 23 with the gaskets, so that theprocessing I chamber 20 and the water jacket space 21 are properlysealed from each other and the surroundings. If a liner becomes worn, itis only necessary to remove the bolts 18 joining the rings 16 and 23 tothe flanges l2 and 14 on the outer jacket 11 to separate the liner 19from the remainder of the vessel 10.

Completing the description of the other components of the sandmill, itcan be seen that the lower end of the mill is closed by a cover assembly30 which is suitably attached to the connecting ring 16. The liquid tobe processed within the processing chamber 20 is fed into the processingchamber through an inlet 33 in the lower cover assembly 30 by means of apump (not shown).

The upper portion of the sandmill includes an upper outer wall or jacket36 and a inner liner 38 attached to the ring 14 and spaced from thejacket 36 by the ring A rotor assembly 42 including a plurality ofindividual rotors v43 mounted on a shaft 44 is supported at the upperend of the vessel by the cover assembly 40, with the rotor assembly 42being driven by motor and pulley arrangement (not shown). A section ofthe upper jacket 36 and the liner 38 are cut away and replaced by acurved screen 46 defining an outlet from the processing chamber 20. Thescreen 46 permits the processed liquid from leaving the vessel whilepreventing the escape of the grinding media within the processingchamber. An outlet enclosure 48 encloses the screen 46, and theprocessed liquid finally leaves the mill through an outlet pipe 50.

In operation it will be apparent from the foregoing that liquid to beprocessed is pumped into the processing chamber 20 through the inlet 33and then upwardly through the grinding media in the chamber and out theoutlet pipe 50. The rotor assembly 42 is continually agitating the sandto provide thorough dispersing of the solid particles within the liquid.When the liner 19 becomes worn by the abrasive action of the grindingmedia, the unit can be simply and easily dismantled in the mannerdescribed to replace the liner.

What is claimed is:

1. A mill for processing liquid including a vessel forming a processingchamber for containing sand or other grinding media, a rotatableimpeller in said chamber for agitating the sand, and an inlet and anoutlet to the chamber for pumping the liquid through the sand, the meansdefining said vessel comprising:

an outer cylindrical jacket;

a cylindrical liner positioned within the jacket and forming the actualprocessing chamber; means spacing said liner from the jacket to define aspace for circulating a heat exchange medium; and

means removably attached to said jacket for closing the ends of thejacket and the liner and sealing the processing chamber from the spacebetween the liner and the jacket, the construction of the closing meansbeing such that upon removal of the connection between the jacket andthe closing means the liner is free to be easily withdrawn from thevessel for repair or replacement.

2. The mill of claim 1 wherein said closing means includes a ring whichis bolted to the end of the vessel, the ring having an annular groove inwhich is positioned a gasket and the end of the liner.

3. The mill of claim 1 including:

an annular flange permanently attached to the ends of the jacket, saidflanges extending inwardly to space the liner from the vessel; and

said closing means includes on each end a member which is attached tothe flanges on the ends of the vessel, said members being formed tocooperate with the ends of the vessel and said flanges to seal the endsof the liner and the jacket.

4. A mill for precessing liquid having a vessel with a processingchamber for containing sand or other grinding media, a rotatableimpeller in said chamber for agitating the media, and an inlet andoutlet to the chamber to permit the pumping of liquid through the mediain the chamber, means defining said vessel comprising:

an outer cylindrical jacket having an annular flange $21323 its ufififiielf oilaizi'lliile illi ing an outer portion which extends outwardlybeyond the cylindrical outer surface of the jacket, each of said flangesfurther including a portion extending inwardly beyond the innercylindrical surface of the jacket;

a lower connecting ring bolted to the bottom of the vessel, the boltsextending into the outer portion of the lower flange, the ring includingan annular groove in its upper surface;

a depending annular rib formed on the inner portion of said lower flangeand extending into said groove;

a cylindrical liner positioned within said vessel and forming theprocessing chamber for confining the grinding media, the lower end ofthe liner being positioned within said groove adjacent said rib;

an upper connecting ring bolted to the upper flange with the boltsextending into the outer portion of said upper flange, the upper ringhaving an annular grove formed in its lower surface;

an upstanding annular rib formed on the inner portion of said upperflange and extending into the groove in said upper ring, the upper endof said liner extending into said annular groove in said upper ringadjacent said upstanding rib; and

gasket means positioned within each of said grooves adjacent the ends ofsaid liner and said ribs to seal the joint formed by the liner, therings and the flanges.

1. A mill for processing liquid including a vessel forming a processingchamber for containing sand or other grinding media, a rotatableimpeller in said chamber for agitating the sand, and an inlet and anoutlet to the chamber for pumping the liquid through the sand, the meansdefining said vessel comprising: an outer cylindrical jacket; acylindrical liner positioned within the jacket and forming the actualprocessing chamber; means spacing said liner from the jacket to define aspace for circulating a heat exchange medium; and means removablyattached to said jacket for closing the ends of the jacket and the linerand sealing the processing chamber from the space between the liner andthe jacket, the construction of the closing means being such that uponremoval of the connection between the jacket and the closing means theliner is free to be easily withdrawn from the vessel for repair orreplacement.
 2. The mill of claim 1 wherein said closing means includesa ring which is bolted to the end of the vessel, the ring having anannular groove in which is positioned a gasket and the end of the liner.3. The mill of claim 1 including: an annular flange permanently attachedto the ends of the jacket, said flanges extending inwardly to space theliner from the vessel; and said closing means includes on each end amember which is attached to the flanges on the ends of the vessel, saidmembers being formed to cooperate with the ends of the vessel and saidflanges to seal the ends of the liner and the jacket.
 4. A mill forprocessing liquid having a vessel with a processing chamber forcontaining sand or other grinding media, a rotatable impeller in saidchamber for agitating the media, and an inlet and outlet to the chamberto permit the pumping of liquid through the media in the chamber, meansdefining said vessel comprising: an outer cylindrical jacket having anannular flange welded to its lower end and an annular flange welded toits upper end, each of said flanges having an outer portion whichextends outwardly beyond the cylindrical outer surface of the jacket,each of said flanges further including a portion extending inwardlybeyond the inner cylindrical surface of the jacket; a lower connectingring bolted to the bottom of the vessel, the bolts extending into theouter portion of the lower flange, the ring including an annular groovein its upper surface; a depending annular rib formed on the innerportion of said lower flange and extending into said groove; acylindrical liner positioned within said vessel and forming theprocessing chamber for confining the grinding media, the lower end ofthe liner being positioned within said groove adjacent said rib; anupper connecting ring bolted to the upper flange with the boltsextending into the outer portion of said upper flange, the upper ringhaving an annular grove formed in its lower surface; an upstandingannular rib formed on the inner portion of said upper flange andextending into the groove in said upper ring, the upper end of saidliner extending into said annular groove in said upper ring adjacentsaid upstAnding rib; and gasket means positioned within each of saidgrooves adjacent the ends of said liner and said ribs to seal the jointformed by the liner, the rings and the flanges.